How to edit "info.dvr" + How to match a particular MPEG format with FFMPEG

[falco2000]

Hello everybody. Third thread of mine.

I own this digital terrestrial TV receiver:

http://www.strong.tv/en/software-doc...rch=srt%205222

When I record a movie, the receiver (set on MPEG-PS mode, not on MPEG-TS mode), creates in a folder "ALIDVR" of the USB device (ex.: a pendrive) connected to it a subfolder dedicated to the movie where it puts:

- a group of .MPG files, named 000.mpg, 001.mpg, and so on, depending on the duration of the movie: they are the actual video and audio content
- a very little file named "INFO.DVR", that (I think) contains additional information such as the TV channel name, the date the movie was recorded, but also a copy of the format settings of the above mentioned ".mpg" files

Infact, if I convert those ".mpg" files keeping all the original settings but changing only the video bitrate, the receiver doesn't play the movie anymore.

Or, more precisely, it doesn't play it anymore if I access the movie through the list of the recordings made by the receive (a function/menu called "Record Manager").
It plays the movie, instead, if I open the file with another "sub-application" of its operating system, called "Media player", that opens MPG, JPG, MP3 and WMA files.

So, the only reasonable deduction, to me, is that I can't play the converted recorded movie because the new video bitrate doesn't match anymore with the information contained in the INFO.DVR file.

I would need to read and edit with my PC this INFO.DVR file to "update" it to the converted MPG files characteristics, hoping that this will let me play the movie like all other "original" recordings.

Does anyone know if and how this could be possible?

Thank you very much

PS: you probably will say "why don't you use the 'media player' to play the converted movies?'. Simply because the receiver can't record while I play a movie with the media player (while it can when I play a movie with the classic "record manager" menu), and this is a problem for me, since I often play movies while recording another live transmission.

EDIT: Read the latest post of this thread, the problem could be the MPEG settings of the converted movie, not the INFO.DVR file.

[aedipuss]

have you tried to open the info.dvr with notepad. it might be a text/xml file.

you can also get the video information with mediainfo. it's free. install and set it to test mode for the complete listing.

[falco2000]

have you tried to open the info.dvr with notepad. it might be a text/xml file.

you can also get the video information with mediainfo. it's free. install and set it to test mode for the complete listing.

Oh, yes, I already tried both your suggestions.

Here's all that Notepad sees (using Notepad++ blank spaces are shown as "NUL" characters: the file is 90% full of them)

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And here is what MediaInfo sees:

General
Complete name : J:\ALIDVR\2012-09-25.13.47.00-MTV MUSIC-3-506\INFO.DVR
File size : 32.0 KiB

No useful information...

Why should this file influence the playback?

[jman98]

Why should this file influence the playback?

I don't think it does. I think I know what your problem is and if I am right, basically you don't correctly understand how your receiver is really working.

However, I feel that there is some chance that I do not understand your situation correctly and if I don't, then my advice to you on this subject would be wrong and useless. I am still hoping that someone else will join this thread. Perhaps we have someone who is familiar with your device. However, if nobody else joins I will try to remember tomorrow to post what I think is really happening.

[aedipuss]

And here is what MediaInfo sees:

General
Complete name : J:\ALIDVR\2012-09-25.13.47.00-MTV MUSIC-3-506\INFO.DVR
File size : 32.0 KiB


No useful information...

that's not the file to get the video's spec from. you need to open the actual video file with mediainfo, not the .dvr thing.

[sanlyn]

I see three problems:

1) The new mpg's do not match the info in the original .dvr file. I don't agree that the dvr file has nothing to do with playback by a certain type of player, any more than I think .ifo files have nothing to do with the way DVD players handle a standard DVD disc. The recording device created the .dvr file for a reason. Meanwhile, the plain-jane MediaPlayer component is similar to WMP; it doesn't look for a .dvr, it just plays the video as-is, with no menus, chapters, titles, or other enhancements.

2) the new mpg's are encoded at a low 700 bitrate which, as I understand it, many (but not all) "standard" dvd playback devices would refuse to play anyway. I thought something like a 2000-1500 bitrate was the minimum for MPEG2 when organized for DVD. Neither of my two MPEG encoders will allow me to specify lower than a 2000 bitrate for DVD-compliant MPEG2. In any case, there's no way I want to watch a fast-action video broadcast at a cheap low bitrate to begin with, originally recorded at an equally stingy 4500 bitrate, then downgraded to a bitrate of 700. The original, unprocessed MPEG2 posted in the earlier thread was painful enough to watch anyway. But now, at 700 it "looks great"? "no quality loss" ? "shouldn't have any effect on quality" ? ? ? ? Gimme a break.

3) The O.P. is visually impaired, and possibly crackers (nothing personal. I write in the clinical sense, although I have no formal medical or psychiatric training). But...to each his own. If the owner likes it and gets a buzz, the project has succeeded in the basic sense.

There have been a rash of similar threads recently. I follow them for the information I might get about processing tips. But there's a reason I hesitate to contribute or comment: Hi, I have an 8-disc DVD set of 32 1-hour movies that I want to reduce to a file size small enough to fit all 32 hours on a 256-kb memory stick I picked up free from a box of cereal. Please advise me as to how I could re-invent and meddle with this technology without compunction or consequence, and use these sophisticated magic-bullet converters and transcoders as weapons of mass destruction.

<End of rant> Enjoy

[falco2000]

I see three problems:

1) The new mpg's do not match the info in the original .dvr file. I don't agree that the dvr file has nothing to do with playback by a certain type of player

Maybe it's not this the problem. Please read what I say below.

2) the new mpg's are encoded at a low 700 bitrate which, as I understand it, many (but not all) "standard" dvd playback devices would refuse to play anyway. I thought something like a 2000-1500 bitrate was the minimum for MPEG2 when organized for DVD. Neither of my two MPEG encoders will allow me to specify lower than a 2000 bitrate for DVD-compliant MPEG2.

Basing on my tests, this is a problem only for MPEG-1 files, not for MPEG-2. Please read what I say below.

In any case, there's no way I want to watch a fast-action video broadcast at a cheap low bitrate to begin with, originally recorded at an equally stingy 4500 bitrate, then downgraded to a bitrate of 700. The original, unprocessed MPEG2 posted in the earlier thread was painful enough to watch anyway. But now, at 700 it "looks great"? "no quality loss" ? "shouldn't have any effect on quality" ? ? ? ? Gimme a break.

The "visual quality" test I did before saying "looks great" etc. was not made with the file I posted. The file that I used during those tests satisfied me when converted, because I don't need an absolute "good quality", just an acceptable one.

3) The O.P. is visually impaired, and possibly crackers (nothing personal. I write in the clinical sense, although I have no formal medical or psychiatric training). But...to each his own. If the owner likes it and gets a buzz, the project has succeeded in the basic sense. [...]

I will ignore these unuseful insinuations, let's focus on technology in this forum, not medicine or psychology. Please avoid judgements if you want to reply to my posts in the future, or just save your time and don't reply at all

Let's come to my technical problems.

These are the original file characteristics:

General
Complete name : C:\xyz\000ori.MPG
Format : MPEG-PS
File size : 5.11 MiB
Duration : 14s 474ms
Overall bit rate mode : Variable
Overall bit rate : 2 962 Kbps

Video
ID : 224 (0xE0)
Format : MPEG Video
Format version : Version 2
Format profile : Main@Main
Format settings, BVOP : Yes
Format settings, Matrix : Custom
Format settings, GOP : M=3, N=12
Duration : 14s 474ms
Bit rate mode : Variable
Bit rate : 2 711 Kbps
Maximum bit rate : 15.0 Mbps
Width : 720 pixels
Height : 576 pixels
Display aspect ratio : 16:9
Frame rate : 25.000 fps
Standard : PAL
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Interlaced
Scan order : Top Field First
Compression mode : Lossy
Bits/(Pixel*Frame) : 0.262
Stream size : 4.68 MiB (92%)

Audio
ID : 192 (0xC0)
Format : MPEG Audio
Format version : Version 1
Format profile : Layer 2
Duration : 14s 337ms
Bit rate mode : Constant
Bit rate : 192 Kbps
Channel(s) : 2 channels
Sampling rate : 48.0 KHz
Compression mode : Lossy
Delay relative to video : -377ms
Stream size : 336 KiB (6%)

Menu

This is what happens when I try lowering the bitrate of the original file using FFmpeg:

1) FFmpeg without parameters converts the file from MPEG-2 to MPEG-1. Why?

2) I added a "c:a copy" parameter (just to be sure that the audio format didn't influenced my tests) and a video bitrate parameter ("b:v ...kbps"): I discovered that my receiver "record manager" reads only those MPEG-1 encoded files at more than 2104 Kbps (while the decoder "media player" reads any bitrate). This is unuseful for me, because this bitrate is often equal to or higher than the original movie, and I don't get and filesize saving.

3) So I removed the bitrate parameter (keeping the "c:a copy" for the audio stream") and added the MPEG-2 encoding parameter (to restore the original MPEG-2 encoding), but my decoder "record manager" didn't read the output file (instead it automatically deleted it!).

4) I noticed that the (not specified by parameters) bitrate of the MPEG-2 encoded made in the point "3)" was 1298 Kbps, so I tried adding a second parameter, an explicit video bitrate, and I did several tests increasing it up to 6000 Kbps, but nothing, the receiver "record manager" always doesn't play the file (it deletes it automatically as I said above). This made me deduce that the MPEG-2 format encoded with FFMPEG was different from the original file one.

5) Here are the video (and other) characteristics of the output file encoded by FFMPEG in MPEG-2 with audio stream simply copied (it's the output file mentioned in point "3)". Please notice which characteristics, in addition to the non-relevant bitrate, are present in the video stream: I highlighted them in bold, both here below and above at the top of the post. Notice the different ones (BVOP, Matrix, GOP, Scantype, Scan order). Maybe one or more of these are responsible for the unplayability of the output movie by the receiver "record manager"?

General
Complete name : C:\xyz\000_mpeg2_audiocopy_NO.mpg
Format : MPEG-PS
File size : 2.70 MiB
Duration : 14s 920ms
Overall bit rate mode : Variable
Overall bit rate : 1 518 Kbps

Video
ID : 224 (0xE0)
Format : MPEG Video
Format version : Version 2
Format profile : Main@Main
Format settings, BVOP : No
Format settings, Matrix : Default
Format settings, GOP : M=1, N=12
Duration : 14s 920ms
Bit rate mode : Variable
Bit rate : 1 295 Kbps
Width : 720 pixels
Height : 576 pixels
Display aspect ratio : 16:9
Frame rate : 25.000 fps
Standard : PAL
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Compression mode : Lossy
Bits/(Pixel*Frame) : 0.125
Stream size : 2.30 MiB (85%)

Audio
ID : 192 (0xC0)
Format : MPEG Audio
Format version : Version 1
Format profile : Layer 2
Duration : 14s 399ms
Bit rate mode : Constant
Bit rate : 192 Kbps
Channel(s) : 2 channels
Sampling rate : 48.0 KHz
Compression mode : Lossy
Stream size : 337 KiB (12%)

6) I searched for TV channels that have video bitrates lower than 2000 kbps: I found 25 channels. The one with the lowest video bitrate has a 526 kbps bitrate. All these 25 channels, from about 1900 kbps down to 526 kbps are correctly recorded and played by the receiver "Record manager" (in MPEG-2 format, like mentioned in the characteristics at point "5") so the playability does NOT depend on video bitrate if the file is encoded (by the receiver or by FFMPEG) in MPEG-2 format. The problem should be in those characteristics that I highlighted in bold above. But I don't know yet how to write the FFMPEG command to match the characteristics of the movie (BVOP, Matrix, GOP, Scantype, Scan order).

7) (additional point) During tests, I also tried creating an FFMPEG output keeping the original video and audio streams ("ffmpeg -i 000ori.MPG -c:v copy -c:a copy 000_videocopy_audiocopy.mpg"), but I got an error that I don't understand:

ffmpeg -i 000ori.MPG -c:v copy -c:a copy 000_videocopy_audiocopy.mpg

ffmpeg version N-44601-gcb3591e Copyright (c) 2000-2012 the FFmpeg developers
built on Sep 19 2012 16:28:01 with gcc 4.7.1 (GCC)
configuration: --enable-gpl --enable-version3 --disable-pthreads --enable-runtime-cpudetect --enable-avisynth --enable-bzlib --enable-frei0r --enable-lib
ass --enable-libcelt --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libfreetype --enable-libgsm --enable-libmp3lame --enable-libnut --enabl
e-libopenjpeg --enable-librtmp --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libutvideo --enable-libvo-aacenc --enable-libvo-amrwb
enc --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxavs --enable-libxvid --enable-zlib
libavutil 51. 73.101 / 51. 73.101
libavcodec 54. 56.100 / 54. 56.100
libavformat 54. 27.101 / 54. 27.101
libavdevice 54. 2.100 / 54. 2.100
libavfilter 3. 16.104 / 3. 16.104
libswscale 2. 1.101 / 2. 1.101
libswresample 0. 15.100 / 0. 15.100
libpostproc 52. 0.100 / 52. 0.100
[mp2 @ 033bfac0] Header missing
[mpeg @ 01ffbe20] max_analyze_duration 5000000 reached at 5016000
Input #0, mpeg, from '000ori.MPG':
Duration: 00:00:14.81, start: 0.128222, bitrate: 2894 kb/s
Stream #0:0[0x1e0]: Video: mpeg2video (Main), yuv420p, 720x576 [SAR 64:45 DAR 16:9], 15000 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc
Stream #0:1[0x1c0]: Audio: mp2, 48000 Hz, stereo, s16, 192 kb/s
Output #0, mpeg, to '000_videocopy_audiocopy.mpg':
Metadata:
encoder : Lavf54.27.101
Stream #0:0: Video: mpeg2video, yuv420p, 720x576 [SAR 64:45 DAR 16:9], q=2-31, 15000 kb/s, 25 fps, 90k tbn, 25 tbc
Stream #0:1: Audio: mp2, 48000 Hz, stereo, 192 kb/s
Stream mapping:
Stream #0:0 -> #0:0 (copy)
Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
[mpeg @ 03377860] pts (33912) < dts (36950) in stream 0
av_interleaved_write_frame(): Invalid argument

So, in short,

- I need an answer for point "1)"
- I understood the problem with MPEG-1 files (point "2")
- I'm stuck with the MPEG-2 problem (points "3)", "4)", "5)"): how can I get an FFMPEG output matching the relevant-for-playability characteristics of the original movies recorded by the receiver?
- I don't understand the error mention in point "7)"

Does anyone can help me? Thank you very much!

Note: all the output files I created with FFmpeg are correctly playable on my PC and the receiver "media player": MPEG-1s, MPEG-2s, even with different bitrates (lower than 2000 kbps too).

[jman98]

2) the new mpg's are encoded at a low 700 bitrate which, as I understand it, many (but not all) "standard" dvd playback devices would refuse to play anyway. I thought something like a 2000-1500 bitrate was the minimum for MPEG2 when organized for DVD. Neither of my two MPEG encoders will allow me to specify lower than a 2000 bitrate for DVD-compliant MPEG2. In any case, there's no way I want to watch a fast-action video broadcast at a cheap low bitrate to begin with, originally recorded at an equally stingy 4500 bitrate, then downgraded to a bitrate of 700. The original, unprocessed MPEG2 posted in the earlier thread was painful enough to watch anyway. But now, at 700 it "looks great"? "no quality loss" ? "shouldn't have any effect on quality" ? ? ? ? Gimme a break.

The true DVD specs require you to sign NDAs so we normal people have had to just guess at their contents. However, no one has yet suggested a LOWER bit rate limit for MPEG-2 for DVD. Upper limits definitely exist, but I've never seen any evidence of a lower limit. As far your "two MPEG encoders" go, that is just talk. Name them. If CCE, for example, says that's not valid that is one thing. If Ulead says it's not valid then that is completely different. And do note that many consumer grade DVD tools are well known for enforcing limits that the format does not. For example, it's relatively easy to find consumer grade DVD authoring programs that refuse to use valid MPEG-1 files in DVD or that enforce GOP limits stricter than the format itself does. So the fact that you have 2 unnamed programs that won't allow you to use anything below 2000 does not necessarily mean that the true DVD specs don't allow this. I have a DVD that I made using an old copy of Scenarist that has DVD valid MPEG-1 video (352x240 at VCD bitrates) and 44.1 kHz audio and I use it for testing purposes. However, many consumer DVD authoring applications would refuse to create the DVD. So we need to be careful when we get into arguments based on "my program won't let you do it, therefore it's illegal".

[sanlyn]

The official DVD spec makes no mention of minimum bitrate for MPEG2 DVD-compliant video. I'm going by warnings I've garnered over the years in messages, documentation, and many other sources. My encoders don't stop me from doing certain things, they just warn me. The point is that I come here to learn how to make it better, not how to keep lowering the bar -- the latter apparently becoming preferred SOP around here. I'll ignore that SOP and stick to established patterns.

Meanwhile, proceed. What's the answer to falco2000's last question?